#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

const int N = 1;
const int M = 1e9 + 7;

map<int, char> m;
int p;
int main()
{
#ifdef LOCAL
    freopen("in.txt", "r", stdin);
    freopen("out.txt", "w", stdout);
#endif
    ios::sync_with_stdio(false), cin.tie(0);
    for (int i = 1; i <= 26; i++)
    {
        m[i] = 'a' + i - 1;
    }

    while (cin >> p)
        cout << m[p];
    cout << endl;
    return 0;
}